The present invention resides in the field of high-pressure, or high-performance, liquid chromatography (HPLC) assays, particularly for the delivery of reagents, diluents, solvents, and other fluids an HPLC instrument and apparatus system. More specifically, the present invention is directed to a fluid handling system for the delivery of solvent fluids with positive pressure to an HPLC instrument.
HPLC is a chromatographic technique used to separate a mixture of compounds in analytical chemistry and biochemistry with the purpose of identifying, quantifying or purifying the individual components of the mixture. Generally, HPLC relies on pumps to pass a pressurized liquid and a sample mixture through a column filled with a sorbent, leading to the separation of the sample components. The active component of the column, the sorbent, is typically a granular material made of solid particles. The components of the sample mixture are separated from each other due to their different degrees of interaction with the sorbent particles. The pressurized liquid is typically a mixture of solvents (e.g. water, acetonitrile, methanol) and is referred to as “mobile phase”. In addition to the composition and temperature of the mobile phase, the fluid pressure of the mobile phase plays a major role in the separation process by influencing the interactions taking place between sample components and sorbent. These interactions are physical in nature, such as hydrophobic (dispersive), dipole-dipole and ionic, most often a combination thereof.
HPLC instruments and techniques have become increasingly sophisticated and complex, allowing for the analysis of multiple portions of a sample, utilizing a variety of different solvent fluids or analyzing a variety of samples with the same or different solvents. Such systems require fluid distribution systems capable of allocating precise amounts of solvents at specific pressures, for extended durations of time, and the ability to switch from one solvent to another.
HPLC systems known in the field often require that the solvent fluids to be used by the instruments be elevated, so as to take advantage of gravity, drawing down the solvent fluids into the instrument, and thus priming the fluid lines of the HPLC instrument.
In view of the above, there remains a need to provide solvents to HPLC instrumentation without the disadvantages noted above and known in the field.